U.S. Department of Energy Office of Biological and Environmental Research

BER Research Highlights


A New Mechanism for Microbial Community Metabolism
Published: December 06, 2010
Posted: January 11, 2011

Outside of laboratories, microbial species rarely exist in isolation. Many important environmental processes are actually mediated by complex communities of microbes. In many cases, two or more species have evolved to perform a cooperative metabolic activity that would be energetically unfavorable for either organism acting independently. Research published in the December 3 issue of Science and led by DOE scientist Derek Lovley of the University of Massachusetts, Amherst, describes a new mechanism by which the bacterium Geobacter metallireducens consumes ethanol, an important intermediate compound in oxygen free soils and sediments, in cooperation with a second organism Geobacter sulfureducens. For this reaction to yield energy for either partner, electrons produced from ethanol oxidation must be rapidly consumed. Although it was previously assumed that the first organism uses a hydrogen production mechanism to pass electrons to its partner, the authors have discovered that electrons are instead directly fed to G. sulfureducens via conductive "nanowires" called pili on the cell surface, resulting in much more efficient collaborative growth. These results provide important new clues on the fundamentals used by microbes to mediate important environmental processes such as carbon cycling and contaminant transformation and suggest intriguing new approaches to direct generation of electricity in microbial fuel cell systems.

Reference: Summers, Z.M., H. E. Fogarty, C. Leang, A. E. Franks, N. S. Malvankar, and D. R. Lovley. 2010. "Direct Electron Exchange Within Aggregates of an Evolved Syntrophic Coculture of Anaerobic Bacteria," Science 330:1413-15.

Contact: Dan Drell, SC-23.2, (301) 903-4742
Topic Areas:

  • Research Area: Subsurface Biogeochemical Research
  • Research Area: Microbes and Communities
  • Research Area: Sustainable Biofuels and Bioproducts

Division: SC-23.2 Biological Systems Science Division, BER

 

BER supports basic research and scientific user facilities to advance DOE missions in energy and environment. More about BER

Recent Highlights

May 10, 2019
Quantifying Decision Uncertainty in Water Management via a Coupled Agent-Based Model
Considering risk perception can improve the representation of human decision-making processes in age [more...]

May 09, 2019
Projecting Global Urban Area Growth Through 2100 Based on Historical Time Series Data and Future Scenarios
Study provides country-specific urban area growth models and the first dataset on country-level urba [more...]

May 05, 2019
Calibrating Building Energy Demand Models to Refine Long-Term Energy Planning
A new, flexible calibration approach improved model accuracy in capturing year-to-year changes in bu [more...]

May 03, 2019
Calibration and Uncertainty Analysis of Demeter for Better Downscaling of Global Land Use and Land Cover Projections
Researchers improved the Demeter model’s performance by calibrating key parameters and establi [more...]

Apr 22, 2019
Representation of U.S. Warm Temperature Extremes in Global Climate Model Ensembles
Representation of warm temperature events varies considerably among global climate models, which has [more...]

List all highlights (possible long download time)